David Root wrote:What is a "good example of a 1st generation amp?
Dumble ODS "generations":
1.
IMO the term "generation" is best suited to refer to a certain kind of
exterior "look" or "design" of the chassis, the cabinet, knobs and switches etc.. I’ve posted a lot of pictures here that show the typical exterior design-specs of each exterior design generation. (I am sorry that you still have to use the search function to find all these pictures and my matching "tone-example-clips". Perhaps in some future a moderator may find the time to organize them in a sticky in the files section. Tony already generously included some of them as examples in his layout threads.)
2.
The more general specs of the circuit of an ODS IMO should be looked upon as being some kind of general "circuit platform" for individualized custom made amps.
3.
The more general specs of this "circuit platform" often changed around the same time when a change in the exterior look took place. No big surprise IMO. A good example is the transition from the "circuit-platform" with what I call the "pre-classic" specs to the circuit-platform with what is called here the "classic" specs.
4.
As a result of this many of the amps with e. g. the "4th generation look" have rather similar technical specs. One of the still unmodified (non-skyline) 4th generation amps may harbour e. g. a what is called here a "low-plate classic" preamp, one may harbour what is called here a "high-plate classic" preamp. And as you know, both of these preamp circuits share a lot of their specs.
5.
As far as my own experience reaches you will meet the more amps with at least a rather similar "circuit-platform" in a certain "design-generation" the more amps of this "design-generation" have been built. No big surprise - just statistics.
Typical 1st generation specs:
Up to now as far as I know only one handful of these early ODS amps with the 1st generation look have surfaced in the sense of "known to a broader public".
And based on only a handful of specimens IMO it makes no sense at all to talk about "typical" specs. The more so IMO, as these amps have been the very first "Overdrive Special" production amps and so IMO the probability seems to be great that at this time in the mid 70ies even the "circuit platform" still may have changed from amp to amp, what IMO means that perhaps it doesn’t even make a lot of sense at all to talk about a common "circuit platform" in regard to the 1st generation ODS amps.
In addition AFAIK there exists some contradicting information concerning these 1st generation amps:
An example:
As far as I remember David Lindley once told, that one of his two well known 1st generation amps is still in its original state (BTW: AFAIK both don’t have a "starve switch" as Tony posted).
Alexander Dumble told this a bit different:
http://www.roblivesey.com/dumble/ (Articles)
"In fact, after the last Steel-String Singer mod I did to David Lindley's amps, he no longer uses the Fender Bassman I Dumbleized for him."
So I fear that perhaps we will never know for sure if someting like "a typical 1st generation circuit" existed at all or what exactly may have been its "typical specs".
And without knowing this it's IMO of course impossible to say wich one of the handful of amps that are known is a "good example of a 1st generation amp" - at least concerning circuit specs.
In regard to building a replica of a Dumble amp that is meant to be a good tool to achieve the "Running On Empty" live tone one way would IMO be to find out in a first step wich one of David's Dumble amps was used and then to find out its specs at the time of the ROE recordings. Another possibility would of course be to start a trial and error process by using the own ears and taste. Another one just to buy a 70ies Bludo or some of the other commercial replicas that claim to be able to deliver the ROE tones - at least if used by a player who knows how to do this.
Cheers
Max
